Why? The Science of Athletics

HUMAN MECHANISM 95 leg was completely revolutionized by that famous quartette of American experts Moloney of Chicago, Garrells of Michigan, Shaw of Dartmouth and Forrest Smithson, who won the Olympic I IO metres title in Igo8 and brought the world's record down to IS secs. Smithson, who was undoubtedly one of the most versatile athletes of his generation, discovered the value of rear hip flexibility through an accident to his hip, and since then high hurdlers have been striving ceaselessly to make their hips more mobile, but no man, either before or since, has been able to get quite the same flexibility as Smithson attained. It will be seen from Fig. I I that the thigh bone, or femur, has a rounded head which fits neatly into the socket, or -acetabulum, of the hip girdle, so that nothing but the stretch on the muscles and ligaments covering and articulating the bones can limit the extent to which FIG. !I a hurdler can raise his leg sideways in the best approved hurdling fashion. The required type of mobility can best be secured by such movements as are set out in Exercises for Athletes (Webster & Heys, John F. Shaw & Co. Ltd., London, 7/6 net). It is, however, only neces– sary to raise the leg upwards and outwards sufficiently for the knee to come level with the hip and the thigh parallel to the ground. Where the arms are concerned a much greater mobility is required, as in such an event as throwing the javelin, in which the delivery is made with the hand and arm fully extended vertically above the shoulder, and that is why the shoulder-joint, although arranged on much the sar.ne principle as the hip-joint, has the upper end of the humerus situated- in a more shallow cup than the acetabulum supplies for the head of the femur. In the case of both joints, however, there is free mobility in all directions.